/// <summary>
/// Decrypt the specified ciphertext, with key and nonce.
/// Uses xchacha20poly1305_ietf_decrypt
/// </summary>
/// <returns>The decrypt.</returns>
/// <param name="ciphertext">Ciphertext.</param>
/// <param name="key">Key.</param>
/// <param name="nonce">Nonce.</param>
public override byte[] Decrypt(byte[] ciphertext, byte[] key, byte[] nonce = null)
{
byte[] message;
if (nonce == null)
{
nonce = GetNonce(ciphertext);
ciphertext = GetCipherText(ciphertext);
}
message = new byte[ciphertext.Length];
long messageLength = ciphertext.Length;
int result = NativeLibsodium.crypto_aead_xchacha20poly1305_ietf_decrypt(
message,
out messageLength,
null,
ciphertext,
ciphertext.Length,
null, 0,
nonce,
key);
if (result != 0)
{
throw new CoflnetException("decryption_error", "Decryption error");
}
return(message);
}
public static byte[] DecryptData(byte[] ciphertextWithNonce, byte[] key)
{
long messageLength = ciphertextWithNonce.Length - X_NONC_ESIZE;
byte[] message = new byte[messageLength];
byte[] nonce = GetNonce(ciphertextWithNonce);
byte[] cipherText = GetCipherText(ciphertextWithNonce);
int result = NativeLibsodium.crypto_aead_xchacha20poly1305_ietf_decrypt(
message,
out messageLength,
null,
cipherText,
cipherText.Length,
null, 0,
nonce,
key);
if (result != 0)
{
throw new DecrytpionError();
}
return(message);
}
public static byte[] DecryptData(byte[] ciphertextWithNonce, byte[] key)
{
long messageLength = ciphertextWithNonce.Length - X_NONC_ESIZE;
byte[] message = new byte[messageLength];
byte[] nonce = ReadBytes(ciphertextWithNonce, 0, X_NONC_ESIZE);
byte[] cipherText = ReadBytes(ciphertextWithNonce, X_NONC_ESIZE, ciphertextWithNonce.Length - X_NONC_ESIZE);
int result = NativeLibsodium.crypto_aead_xchacha20poly1305_ietf_decrypt(
message,
out messageLength,
null,
cipherText,
cipherText.Length,
null, 0,
nonce,
key);
if (result != 0)
{
throw new Exception("Decryption error");
}
return(message);
}